1. Field of Invention
The present invention relates to an external airbag cushion for a vehicle which is deployed forward from a front bumper of the vehicle to absorb shock on impact.
2. Description of Related Art
External airbag are provided in front bumpers of vehicles. Such an exterior airbag is deployed forward when detecting danger of collision, thus protecting the vehicle on impact.
FIG. 1 is an exploded perspective view of an external airbag of the related art and the external airbag is disposed inside a bumper, and in detail, an airbag module on the back beam of the bumper unfolds and inflates outward from the bumper through an unfolding guide.
FIG. 2 is a view showing an external airbag cushion of the related art, which has been developed by the applicant(s), but not published yet, in which a cushion is formed in a box shape and transversely unfolds along the front of the bumper of a vehicle, covering the bumper.
Further, the external airbag has a plurality of chambers separated by separation walls inside and a gas independently flows into the chambers, thereby preventing the entire cushion from bending or folding to one side.
Further, variable vents are formed at the sides to sufficiently absorbing shock after rapid unfolding, so that the variable vents open and the gas is discharged, when the internal pressure increases to a predetermined pressure or more. Further, common vents are formed toward the bumper to effectively absorb shock after the airbag cushion unfolds and to protect the vehicle on impact.
However, such an airbag cushion of the related art has a problem in that pressure is excessively concentrated on a specific chamber, so that the airbag may be broken, and the higher the hitting speed, the faster the internal pressure increases, to that it is difficult to deal with various hitting speeds with the existing venting structures in the actual situations.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.